Linux多线程编程快速入门

  //pthread_self直接返回调用线程的ID  include <pthread.h>  pthread_t pthread_self(void);

  //pthread_equal如果t1和t2所指定的线程ID相同，返回0；否则返回非0值。  include <pthread.h>  int pthread_equal(pthread_t t1, pthread_t t2);

  #include <pthread.h>  int pthread_create(pthread_t *thread, const pthread_attr_t *attr,   void *(*start_routine) (void *), void *arg);

  thread(输出参数)，由pthread_create在线程创建成功后返回的线程句柄，该句柄在后续操作线程的API中用于标志该新建的线程；   start_routine(输入参数)，新建线程的入口函数；   arg(输入参数)，传递给新线程入口函数的参数；   attr(输入参数)，指定新建线程的属性，如线程栈大小等；如果值为NULL，表示使用系统默认属性。

  成功，返回0；   失败，返回相关错误码。

  #include <stdio.h>  #include <stdlib.h>  #include <pthread.h>  #include <unistd.h>    void printids(const char *s){   pid_t pid;   pthread_t tid;   pid = getpid();   tid = pthread_self();   printf("%s, pid %lu tid %lu (0x%lx)n",s,(unsigned long)pid,(unsigned long)tid,   (unsigned long)tid);  }    void *thread_func(void *arg){   printids("new thread: ");   return ((void*)0);  }  int main() {   int err;   pthread_t tid;   err = pthread_create(&tid,NULL,thread_func,NULL);   if (err != 0) {    fprintf(stderr,"create thread fail.n");   exit(-1);    }   printids("main thread:");   sleep(1);    return 0;  }

  gcc -o thread thread.c -lpthread

  main thread:, pid 889 tid 139846854309696 (0x7f30a212f740)  new thread: , pid 889 tid 139846845961984 (0x7f30a1939700)

  include <pthread.h>  void pthread_exit(void *retval);

  include <pthread.h>  int pthread_join(pthread_t thread, void **retval);

  thread(输入参数)，指定我们希望等待的线程   retval(输出参数)，我们等待的线程终止时的返回值，就是在线程入口函数中return的值或者调用pthread_exit函数的参数

  成功时，返回0   错误时，返回正数错误码

  #include <pthread.h>  int pthread_detach(pthread_t thread);

  /*  * 文件名： thread_sample1.c  * 描述：演示线程基本操作  */  #include <stdio.h>  #include <stdlib.h>  #include <unistd.h>  #include <pthread.h>    /*子线程1入口函数*/  void *thread_routine1(void *arg)  {   fprintf(stdout, "thread1: hello world!n");   sleep(1);   /*子线程1在此退出*/   return NULL;  }    /*子线程2入口函数*/  void *thread_routine2(void *arg)  {     fprintf(stdout, "thread2: I'm running...n");   pthread_t main_thread = (pthread_t)arg;     /*分离自我，不能再被连接*/   pthread_detach(pthread_self());     /*判断主线程ID与子线程2ID是否相等*/   if (!pthread_equal(main_thread, pthread_self())) {    fprintf(stdout, "thread2: main thread id is not equal thread2n");   }     /*等待主线程终止*/   pthread_join(main_thread, NULL);   fprintf(stdout, "thread2: main thread exit!n");     fprintf(stdout, "thread2: exit!n");   fprintf(stdout, "thread2: process exit!n");   /*子线程2在此终止，进程退出*/   pthread_exit(NULL);  }    int main(int argc, char *argv[])  {     /*创建子线程1*/   pthread_t t1;   if (pthread_create(&t1, NULL, thread_routine1, NULL)!=0) {    fprintf(stderr, "create thread fail.n");    exit(-1);   }   /*等待子线程1终止*/   pthread_join(t1, NULL);   fprintf(stdout, "main thread: thread1 terminated!nn");     /*创建子线程2，并将主线程ID传递给子线程2*/   pthread_t t2;   if (pthread_create(&t2, NULL, thread_routine2, (void *)pthread_self())!=0) {    fprintf(stderr, "create thread fail.n");    exit(-1);   }     fprintf(stdout, "main thread: sleeping...n");   sleep(3);   /*主线程使用pthread_exit函数终止，进程继续存在*/   fprintf(stdout, "main thread: exit!n");   pthread_exit(NULL);      fprintf(stdout, "main thread: never reach here!n");   return 0;  }

  thread1: hello world!  main thread: thread1 terminated!    main thread: sleeping...  thread2: I'm running...  thread2: main thread id is not equal thread2  main thread: exit!  thread2: main thread exit!  thread2: exit!  thread2: process exit!